# #3f179b

A color — cool, vivid, technical, modern. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#3f179b`
- RGB: rgb(63, 23, 155)
- HSL: hsl(258, 74%, 35%)
- OKLCH: oklch(0.366 0.19 286)
- Relative luminance: 0.0404
- Nearest named color: Galactic Civilization (#442288, Δ 3.689) — https://brandsweets.com/colors/galactic-civilization
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/3f179b

## Tints & shades

- Tints (toward white): #4a1bb6, #5620d5, #6733e1, #7b4ee4, #926de9, #a687ed, #baa2f1, #cdbcf5, #e5dcfa, #f8f6fe
- Shades (toward black): #39158e, #341381, #2f1173, #290f66, #240d59, #1d0b47, #17093a, #12072c, #0d051f, #070312

## Harmonies

- Complementary: #749b17
- Analogous: #17329b, #81179b
- Triadic: #9b3f17, #179b3f
- Split-complementary: #9b8117, #329b17
- Tetradic: #9b1732, #749b17, #179b81

## Colors that go with #3f179b

Named partners (harmony on the OKLCH wheel, co-occurrence in curated palettes and brand systems, and the neutrals that carry it), best first:

- **Royal Blue** #4169e1 [harmony, pool: analogous] — Royal Blue is #3f179b's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Discord (https://brandsweets.com/colors/brands/discord), Nivea (https://brandsweets.com/colors/brands/nivea-com), Nokia (https://brandsweets.com/colors/brands/nokia-com), NHL (https://brandsweets.com/colors/brands/nhl-com). — https://brandsweets.com/colors/royalblue
- **Blue** #0000ff [pool] — 4 real palettes, including Zillow's brand system and Procter & Gamble's brand system put Blue beside #3f179b, as the lead colour. Seen in: Zillow (https://brandsweets.com/colors/brands/zillow-com), Procter & Gamble (https://brandsweets.com/colors/brands/pg-com), Pfizer (https://brandsweets.com/colors/brands/pfizer-com), CVS (https://brandsweets.com/colors/brands/cvs-com). — https://brandsweets.com/colors/blue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #3f179b: 5 real palettes, including Tide's brand system and Zillow's brand system, as the lead colour. Seen in: Tide (https://brandsweets.com/colors/brands/tide-com), Zillow (https://brandsweets.com/colors/brands/zillow-com), Purina Pro Plan (https://brandsweets.com/colors/brands/chewy-com), Unilever (https://brandsweets.com/colors/brands/unilever-com). — https://brandsweets.com/colors/cobalt
- **Crimson** #dc143c [pool] — Crimson is paired with #3f179b in 7 real palettes, including Pepsi's brand system and Casper Sleep's brand system, as the supporting colour. Seen in: Pepsi (https://brandsweets.com/colors/brands/pepsi-com), Casper Sleep (https://brandsweets.com/colors/brands/casper-com), Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #3f179b: 4 real palettes, including Warbyparker's brand system and Unilever's brand system, as the accent. Seen in: Warbyparker (https://brandsweets.com/colors/brands/warbyparker-com), Unilever (https://brandsweets.com/colors/brands/unilever-com), Slack (https://brandsweets.com/colors/brands/slack-com), Bank of America (https://brandsweets.com/colors/brands/bankofamerica-com). — https://brandsweets.com/colors/denim
- **Steel Blue** #4682b4 [pool] — Designers have shipped Steel Blue with #3f179b: 4 real palettes, including FedEx's brand system and Hershey's's brand system, as the accent. Seen in: FedEx (https://brandsweets.com/colors/brands/fedex-com), Hershey's (https://brandsweets.com/colors/brands/hersheys-com), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Glacier (https://brandsweets.com/palettes/cool#glacier). — https://brandsweets.com/colors/steelblue
- **Olive Green** #808000 [harmony: complementary] — Olive Green sits directly opposite #3f179b on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. — https://brandsweets.com/colors/olive
- **Charcoal** #36454f [role, pool] — Charcoal is the text near-black for #3f179b: softer than #000 and cool enough to feel like part of the same palette. Seen in: dbt Labs (https://brandsweets.com/colors/brands/getdbt-com), Boeing (https://brandsweets.com/colors/brands/boeing-com). — https://brandsweets.com/colors/charcoal

## Contrast (WCAG 2.x, as text)

- On white (#ffffff): 11.62:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.81:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #855be6 (4.64:1); AA: background → #a3a3a3 (4.61:1); AAA: text → #a687ed (7.31:1); AAA: background → #c9c9c9 (7.02:1)

## Brands using this color

- **dbt Labs** — accent #3d189a (Δ 0.408) — https://brandsweets.com/colors/brands/getdbt-com

## Fonts for this mood

- technical: https://brandsweets.com/fonts/mood/technical
- modern: https://brandsweets.com/fonts/mood/modern

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/3f179b-ad9cc4-dfc44e-291f2d-e9ebf1?lock=0&style=vibrant
(Humans lock/regenerate in the tool; the URL is the state — read `lock=` back to see what they kept.)

## Connect an agent

Point any MCP client at the BrandSweets colors endpoint for the same engine:

- Endpoint: https://mcp.brandsweets.com/colors/mcp
- Tools: `analyze_color` (e.g. `analyze_color({ color: "#3f179b" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.